1. Field of the invention
This invention relates to an electric shaver, and more particularly to an electric shaver providing a mechanism for regulating cutter driving speed, i.e. movable cutter driving speed against a fixed cutter.
2. Description of the prior art
It is known that the cutting quality of an electric shaver is influenced upon the driving speed of the movable (inner) cutter and moreover the optimum driving speed is varied upon the thickness of the beard to be cut.
Table 1 illustrates differences in after-shave feelings for persons who have thick or light beards; for instance, those who have heavy beards insist that the slower (L) the inner cutter driving speed, the shorter the beard is cut. On the contrary, those having light beards assert that the faster (H) the driving speed, the shorter the beard is cut. Thus the feeling is individually diversified.
TABLE 1 ______________________________________ Criterion Driving speed Heavy beard Light beard ______________________________________ Sharp H ##STR1## L Short H L ##STR2## Quick H ##STR3## L Smooth H L ##STR4## Soft H L ##STR5## Catching H L ##STR6## ______________________________________
However, it is difficult to simply change the inner cutter driving speed in conventional electric shavers. Attempts were made to improve after-shave feeling by attaching a trimmer for cutting sideburns in agreement with the portion where the beard is shaven or a comb cutter on the periphery of the fixed (outer) cutter for guiding the beard (for instance, see U.S. Pat. No. 3,552,007). These attempts do not concern to change the driving speed of the movable cutter.